They said the park's meager three toilets led some to relieve themselves in bushes and on buildings. But the backlash has already started with six civic groups teaming up in a letter to the city that says the urinal must go.

They claim the urinal is a flagrant violation of the law and basic public policy, is unsanitary and discriminates against women and children because it is not designed for females.

“This is more than stunning and disgusting. It's a human regression of mankind,” said Frank Lee with the Pacific Justice Institute, one of the groups that joined forces in protest. “If this is not stopped, this will become the norm in San Francisco and spread to other cities.”

Brad Dacus, president of Pacific Justice Institute, called it a “new low even for San Francisco.”

“It is also blatantly illegal,” he said. “The city has not even attempted to comply with its own ordinances, much less state or federal law. We intend to hold them accountable. Public urination is bad enough; spending taxpayer money to promote it is indefensible.”

“Honestly, we were ready to go pee anywhere,” San Francisco resident Aaron Cutler told news station KNTV after the urinal was installed. “So any facility is better than none.”

San Francisco Recreation & Parks Department spokeswoman Sarah Madland said Thursday that the urinal cost $15,000 to install, and so far there have been five emailed complaints about it. A representative from the San Francisco city attorney's office was not immediately available for comment Friday.

The open-air urinal is part of a $20-million renovation plan that now has put more than two dozen toilets in Dolores Park, along with other upgrades.